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Biological Conversion Process of Methane Into Methanol Using Mixed Culture Methanotrophic Bacteria Enriched from Activated Sludge System

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Biological Conversion Process of Methane Into Methanol Using Mixed Culture Methanotrophic Bacteria Enriched from Activated Sludge System BIOLOGICAL CONVERSION PROCESS OF METHANE INTO METHANOL USING MIXED CULTURE METHANOTROPHIC BACTERIA ENRICHED FROM ACTIVATED SLUDGE SYSTEM Ahmed Mohamed AlSayed Mahmoud A THESIS SUBMITTED TO THE FACULTY OF GRADUATE STUDIES IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF APPLIED SCIENCE GRADUATE PROGRAM IN CIVIL ENGINEERING YORK UNIVERSITY, TORONTO, ONTARIO AUGUST 2017 © Ahmed AlSayed, 2017 Abstract Wastewater treatment plants contribute to the global warming phenomena not only by GHG emissions, but also, by consuming enormous amount of fossil fuel based energy. Therefore, methane bio-hydroxylation has attracted the attention as methanol is an efficient substitute for methane (GHG) due to its transportability and higher energy yield. This work is destined to investigate and optimize the factors affecting the microbial activity within methane bio-hydroxylation system using type I methanotrophs enriched from activated sludge system. The optimization resulted in a notable enhancement of the growth kinetics. The -1 attained maximum specific growth rate (µmax) (0.358 hr ) and maximum specific methane -1 biodegradation rate (qmax) (0.605 g-CH4,Total/g-DCW/hr ) were the highest reported in mixed cultures. Furthermore, the maximum methanol productivity achieved is comparable with pure cultures and equal to 2115±81 mg/L/day. Whereas, methanol concentration of 485±21 mg/L was attained which is two times higher than the reported using mixed culture. ii Dedication " Bountiful is your life, full and complete. Or so you think, until someone comes along and makes you realize what you have been missing all this time. Like a mirror that reflects what is absent rather than present, he shows you the void in your soul—the void you have resisted seeing. That person can be a lover, a friend, or a spiritual master. Sometimes it can be a child to look after. What matters is to find the soul that will complete yours. All the prophets have given the same advice: Find the one who will be your mirror! " Thank you Issraa (my wife) and Yousr (my daughter) for being that person who complete my soul and make me feel the true meaning of love and happiness by just being in my life. iii Acknowledgment “ .” Surah Al-Insan, Verse 30 All praise is to Allah, the Almighty, the Most Gracious and the Most Merciful, who gives me the chance to go through the experience of this thesis, Alhamdulillah. It was said that “Sometimes Allah gives while he is actually depriving you, and sometimes He deprives you in giving.”. So, I have to remind myself always that It all given by Allah not me and It is much more important to have pure sole and humble attitude. Dr. Ahmed ElDyasti: I would like to show my appreciation and gratitude to you for your continuous and non- conditional support. You have been always more than an academic supervisor, I can say a big brother or a mentor. Working under your supervision made me learn a lot both in professional and personal aspects. Issraa (my wife): I have to admit, without you, I would not be able to do even 10% of what I did. You have been always supportive and helpful. Actually, no words can describe my appreciation to you. Truly, every success I made was owing to you, after Allah. As I am always saying, my life is just a reflection of you. Soso, I truly love you and extremely proud of you. Thank you for being my life. Yousr (my daughter): You have been and will always be my source of passion, love, and happiness. Nothing makes me feel happy more than being with you. My parents: No words can describe my gratitude and appreciation to them, without whom I would not have reached this point. My father, the man who taught me how to be a person before being an engineer. My mother for her magical ways of support and for being always there to help and support. Dad and Mum, I can always feel your endless prayers and unbounded love and encouragement. I understand how hard it is to live far from each other but you are always in me because simply I am part of you. Thank you for being my parents and for every single good thing I have is because of both of you. Fatma (my sister), Mayan and Omar (her kids): Thank you for being in my life, for giving me a larger circle of love and support. Fatma, you have been always my sister, kind of my mentor. I still remember every single help you gave to me throughout my years in the faculty, and even in the school. You have been always my backbone and your love has been always unconditional. Thank you for being my sister. iv Fergala: You have contributed to every single chapter throughout this thesis in different ways. Thank you for being a perfect research partner and for the hundred hours we spent discussing our plans and experiments. My Friends: Moomen (My Competitor ;D), Nader (The presentations Man), Khaled (The hesitation Man), Zizo (The science man), Zaki (Ebn el Nas el Kowisen), and Waleed (El Shab7), truly you make Canada and York feels like home. Thank you for the good and bad, rich and poor days we spent together. Our Great Research Team: Parin, Parnian, Basma, Zaid, Saif, and Adham, thank you so much for the support you gave to me, you have been always helpful and truthful. Finally, I believe that the most important thing throughout any experience is the people and, Alhamdulillah, throughout my master’s study period, I met a lot of good people, very little bad ones, and made truthful friendships. That’s make me believe that my experience throughout my study at YorkU was successful regardless the academic achievement. v Table of Contents Abstract ............................................................................................................................... ii Dedication .......................................................................................................................... iii Acknowledgment ............................................................................................................... iv List of Tables ....................................................................................................................... x List of Figures .................................................................................................................... xi Chapter 1 Introduction and Justification ........................................................................... 1 1.1 Background ........................................................................................................... 1 1.1.1 Methane as Greenhouse Gas ........................................................................... 1 1.1.2 GHG Emissions from Wastewater Treatment Plants ...................................... 1 1.1.3 Bio-Methane as a Resource in Wastewater Treatment Plants ......................... 2 1.1.4 Methanol as Prominent Substitute for the Bio-Methane ................................. 3 1.1.5 Methanotrophs as Bio-Catalysts for Methane Hydroxylation......................... 4 1.2 Research Rationale ................................................................................................ 5 1.3 Research Objectives .............................................................................................. 7 1.4 Research Approach and Thesis Layout ................................................................. 8 Chapter 2 Literature Review .............................................................................................. 9 2.1 Methanotrophs ....................................................................................................... 9 2.2 Methanotrophs Taxonomy ................................................................................... 10 2.2.1 Type I Methanotrophs ....................................................................................11 2.2.2 Type II Methanotrophs .................................................................................. 12 2.2.3 Type III Methanotrophs ................................................................................. 13 2.2.4 Anaerobic Methanotrophs ............................................................................. 14 2.3 Methane Metabolism in Methanotrophs ............................................................. 14 2.4 Factors Affecting Methanotrophs Growth ........................................................... 21 2.4.2 Temperature ................................................................................................... 23 2.4.3 pH and Salinity .............................................................................................. 23 2.4.4 Substrates ...................................................................................................... 24 2.4.5 Methane to Oxygen Ratio ............................................................................. 25 vi 2.4.6 Methane Solubility ........................................................................................ 26 2.4.7 Nitrogen Sources ........................................................................................... 27 2.4.8 Copper ........................................................................................................... 29 2.5 Bio-Methanol Production Metabolism ................................................................ 30 2.6 Factors Affecting Bio-Methanol Production ....................................................... 32 2.6.1 Bacterial Strains ............................................................................................ 32 2.6.2 pH and Temperature .....................................................................................
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